Dowser-closing mechanism for motion-picture-projecting machines



' 1,658,594 T. L. FEENEY ET AL DOWSER CLOSING MECHANISM FOR MOTION PICTURE PROJECTING MACHINES 3 Sheets-Sheet 1 Filed Dec. 2Q. 1926 WITNES 5Z5:

- 77 .L mggwoks I zomas 50126 62 y 5. 94 g/ umbm Gvdog,

T. L. FEENEY ET AL,

DOWSER CLOSING MECHANISM FOR MOTION PICTURE PROJECTING MACHINES Filed Dec. 20. 1926 3 Sheets-Sheet 2 FIG. 2

Feb. 7, 1928. 1,658,594

T. L. FEENEY ET AL DOWSER CLOSING MECHANISM FOR MOTION PICTURE PROJECTING MACHINES Filed Dec. 20; 1926 3 Sheets-Sheet 3 TIC% i:

WITNES 52's: INVENTORS:

71 01/115 Lewis fihvu'y 4v ATT'oRNEY 5 17123512117? fivdoy, Z I I 3 Patented Feb. 7, 1928. v I A 1,658,594 7 UNITED STATES PATENT OFFICE.-

ASSIGNORS. BY MESNE ASSIGNMENTS, TO ,SENTRY SAFETY CONTROL CORPORA- TION, F PHILADELPHIA, PENNSYLVANIA.

DOWSER-CLOSING MECHANISM FOR MOTION -PICTURE-PROJ ECTIN G MACHINES.

A'pplicatiim filed December'2 0, 1926. Serial No. 155,779.

Our invention relates to safety devices for is mounted. A lamp 9 is mounted on the 55 motion picture projectors and more particumachine so that its cone 10 is directed tolarly to means for automatically interceptward. the aperture in frame 7 through which ing the rays of light passing through the the pictures are projected onto the screen.

0 film 'in case the film feeding mechanism A safety device 11 is mounted on cone 10 ase to fun tion, and is similar to the device described in 50 It is a well known fact that, if the motion Patent N 0. 1,618,417. picture film ceases to move through the path A motor 12 is mounted on the under side of the light rays, the intense heat from the of a base plate 13 forming a part of main lamp will cause the film to explode. In frame 5 and has a pulley l4 rigidly secured Patent No. 1,618,417, issued to us on Febru to its armature shaft. A belt 15 connects ary 22, 1927, we have described a device for pulley 14 to a pulley 16 mounted on a jack intercepting the rays of light between the shaft 17 forming a part of the speed control lamp and the film and for automatically mechanism of the projecting machine. A 15 stopping the motor, in case the film breaks driving pulley (not shown) is also mounted at any point. on jack shaft 17 andi'sconnected by means .Should the mechanism which moves the of a belt 18 to a pulley 19 which operates the film feeding mechanism be stopped for any projecting mechanism in frame 7.

cause, such as the blowing of a fuse or the One side of belt 18 is engaged by a de- -breaking of .a' belt, the film would remain flector sheave 21rotatably mounted on a stationary in the path of the light rays and stub shaft 20 secured in main frame 5. An

would explode from the intense heat. arm 22 is rotatably mounted on shaft 20 The object of this invention is to provide and carries a roller 23 on its outer end which novel mechanism which when the belt breaks tends to bend belt 18 over sheave 21, due to 25 or when the motor circuit is broken will op' a suitable spring arrangement, and keeps the erate to close the dowser to obstruct the rays belt taut. With exception of safety device 30 of light and thus protect the film. 11, all of the elements so far described are A further-object of the invention is toparts of-a standard motionpicture projector provide a device which may be readily and form no part of our invention. The 0 mounted on a motion picture projector and main unit 24 of our device is mounted on the which will utilize the operation of certain upper side of base plate 13 and has one end moving parts of such machine. of a flexible conduit 25 secured to the cover hese objects, and other advantageous 27 of its casing 26 ;',the.other end of the conends which will be described hereinafter, we duit being suitably connected adjacent attain in the following manner, reference safety device 11 as shown in Figure 4.

bclng had to the accompanying drawings in Referring now to Fi ur s 2 nd 3, an

WhlCll electromagnet 28 is mounted in an iron Figure 1 is a fragmentary side view of a frame 29 secured to the bottom of casing 26. motion picture projector on which both our A shaft 30 is mounted through the sides of new invention and the device described in casing 26 and has an armature 31 hinged Patent N 0. 1,618,417 are installed. thereon and adapted to rest uponthe upper Figure 2 is. a top plan view of the main end of magnet frame 29. A non-metallic unit of our device with the casing cover redisk 32 is placed above magnet 28 and has moved and the casing walls shown in section, an aperture through its center to accommo- Figure 3 a section on line-3-3 of Figure ate magnet core 33 which extends beyond 2, certain parts being broken away, and the end of magnet 28 but is sli 'htly spaced igure 4 a combined wiring diagram and from the bottom of armature 31.

diagrammatic view showing the operation A spring 34 has one end connected to one of our device. end of the frame of armature31 and has its Referring now more particularly to Figother end connected to the bottom of easing ure. 1, the projecting machine consists of a 26, thus tending to draw the end of the main frame. 5 carrying a reel case 6 above frame downwardly and raise armature 31 which is mounted a film feeding mechanism away from magnet frame 29. A spring wire frame 7, on top of which the film magazine 8 35 has one end rigidly connected to the other end of the frame of armature 31, extends switch to power wire B, thus energizing upwardly hroughconduit 25 and terminates magnet 28 which will hold armature 31 in a button 36 dlsposed immediately beneath firmly against the. top of frame 29.

a trip arm 37, forming a part of safety de-' Referring now to all the views simultanevice. 11. v r F ously, will be noted that roller 52 is sup- 70 A shaft 38' is mounted in casing 26 and ported by the upper side of belt 15. In has a lever 39, made of insulating material, case this belt breaks, roller 52 would swing r'ockably mounted thereon. A contact 40 is ownwardlyand force cam 50 against lever 38.)

, .yieldingly secured to one end of lever 39' by and raise contact 40 away from contact 47,

means of a stud 41 threaded into the lever thus breaking the circuit through I electro- 75 and encircled by a spring 42 disposed bemagnet 28 and tie-energizing same; thus altween the top '0 contact 40 and a washer 43 lowin 'spring 34 to rock armature 31 on held near the top of thestud by a suitable shaft and force wire upwardlynntil arm 37 and actuates nut, A screw 44 is threaded through the button 86 engages trip '15 rear end of contact andis slidable in a safety device 11., causing tlie doi nser plate 80 recess 45 formed in lever 39 to prevent rota-- to swing downwardly and intercept the tion of the contact and also to provide a of light passing through the film. binding post for the wire 56. Abracket 46, Should blt- 18 break," roller 23 will be almade of insulating material, is secured to lowed to swing outwardly and downwardly 2 the bottom of casing 26 and a contact 47 so that it wouldstrikc extcnsionli? and cause 65 secured to same makes contact with the conlever 39 to rock on, shaft 38; thus breaking tact 40. 'A tension spring 48 has one end the contact between points 40 and 47 and connected to lever 39-and its other end concausing safety device 11 to operate as above nected to the bottom of casing'26 and tends described. The motor circuit is provided 25 to hold contact 40 firmly against contact 47 with a fuse I and, should this fuse blow, the 0 and, by acting against the tension of spring magnet 28. will be de-energized and the 42, absorbs the vibrations of thevmachine. safety device caused to operate.

A shaft 49 is revo'lubly mounted in casing When the weight of either roller 23' or 52 26 and has acam 50 fixed near its center is removed'from lever 39, spring 48 tends to v30 adapted to engage the upper side of lever 39, erk contact 40 against contact 47. The 95 cause same to rock on shaft 38 and raise blow thus produced is softened by the action contact 40 above contact 47 A lever arm 51 of spring 42 while screw 44 prevent-s conis rigidly connected tothe outer end of shaft tact 40 from rotating. 49 and has a roller 52rotatably mounted on With our invention installed on a motion 35 its outer end. An extension 53 is secured to picture projector, it isevident that all dan- 1 lever 39 and extends outwardly through. a ger of the film exploding, due to'the stopsuitable aperture in casing 6.- ping of the film feeding mechanism, is elim- Referring no to Figure 4, the wires A mated. The parts added to the regular and B represent the motor feed circuit and equipment of the machine are few and sim- 40 are connected by the switch C to wires A ple, the device ispositive in action and re- 10,-,

and B. Wire B isc-onnected to one side quires no attention. 0f. a switch insafety device 11 and a wire 0f course the dowser closing mechanisn'i 54 connects theother side of this switch to illustrated may be modified in various ways one side of motor 12. The other side of mowithout departing from the invention herein 4 I 45 tor 12 is connected to wire A- by a wire 55, set forth and hereafter claimed. 110 thus furnishing-power to the motor. \Ve claim:

One end of the prnnary coil ofatransform- 1. In a motion picture projecting machine er T- isconnected to wire 55 and theother having film feeding mechanism, bolting for r end to wire 54, thus putting the transformer the same, and a safety device comprising a,

50 in parallel with m9tor 12. The secondary dow'ser and atrip arm'for releasing the dow- 11:, coil of transformer T is connected to an ser, a spring actuated shaft tending to acelectromagnet in safety device 11 which. is tuate saidtrip arm, electrical means for holdadaptedto actuate this device when this ci-rmg said shaft against the action of the cuit is closed by either of the switches D or spring, and means released'by the breaking 5 E, as described 1n Patent No. 1,618,417. of a1 belt or failure of electric current for 12( A wire 56 connects one terminal of elecreleasing said shaft to'oper'ate said trip arm. tromagnet 28 to wire 54 and a wire 57 con- 2. In ZLmQtlOHPlCtUIG projecting machine nects its other terminal with contact'-47.'- A' having film feeding mechanism, belting for v wire 58 connects contact,40 with wire 55, the same, and a safety device comprising a 60' thus connecting electromagnet 28 inparallel dowser and altrip arm for releasing said 12 with motor 12 and allowing a current to flow 'dowser, means for tripping the arm, a. spring from wire A, through switch C, wire A], urgingsaid last means against said trip arm, wire 55, wire. 58, contacts 40 and 47, wire electrical means for holding said last means 57, electromagnet 28, wire 56, wire 54, the against the act-ion ofthe spring, and means 7 i switch 'in safety device 11, wire B, and operated by the breaking of a belt for open- 1:

engaging the belt ing the electrical circuit to permit said spring to operate said trip ing means.

In a device of the class described, an electromagnet, an armature hinged above the magnet and held in its lowermost position by the attraction of the magnet, a flexible shaft secured to the armature, a spring tending to move the shaft upwardly, an electrical circuit for supplying, current to the magnet, and a pair of contacts in the circuit, whereby separating the contacts will deprive the magnet of its power and allow the spring to move the shaft upwardly. c

4 In a device of the class described, an electromagnet, an armature hinged above the magnet and held in its lowermost position by the attraction of the magnet, a flexible shaft secured to the armature, a spring tending to move the shaft upwardly, a fixed contact, a rockable contact, spring means tending to hold the contacts together, resilient means for cushioning the effect of said spring means, and wires connecting said contacts and said electromagnet to a source of electric power, whereby separation of the contacts or failure of the power will allow said spring to move the flexible shaft upwardly.

5. In combination With a motion picture projectorhaving a motor, a belt and a safet device adapted to intercept the rays of light passing through the machine; means for actuating the safety device including a flexible shaft; a spring tending to move the shaft upwardly and actuate the safety device; an electromagnet tending to hold the shaft against upward movement; a fixed contact; a rockable contact engaging the fixed contact; wires connecting the contacts and electromagnet to a source of power to form a circuit; and means engaging the belt and adapted -to separate the contacts upon the breaking of the belt, whereby the magnet will be de-energized and allow the spring to move the shaft upwardly.

(i. In combination with a motion picture projector having a motor, a belt and a safety device adapted to intercept the rays of light passing through the machine; means for actuating the safety device including a flexible shaft; a spring tending to move the shaft upwardly and actuate the safety device; an electromagnet tending to hold the shaft against upward movement; a fixed contact; a rockable contact engaging the fixed contact; wires connecting the contacts and electromagnet into a circuit; said circuit being connected to the source of power supplying current to the motor; and means and adapted to separate the contacts upon the breaking of the belt, whereby the separating of the contacts or interruption of current to the motor will deenergize the magnet and allow the spring to move the shaft upwardly.

7. In combination with a motion picture projector having a motor, abelt and a safety device adapted to intercept the rays of light passing through the machine; means for actuating the safety device including a flexible shaft; a spring tending to move the shaft upwardly and actuate the safety device; an

electromagnet ten-ding to hold the shaft adapted to engage the arm and separate the contacts upon the breaking of the belt, whereby the magnet will be do-energized and allow the spring to move the shaft upwardly.

8. In combination with a motion picture projector having a motor circuit and a safety device having a dowser and a trip arm for releasing the dowser, means for actuating the safety device including tripping means adjacent the trip arm, a spring tending to move the tripping means against the trip arm, and an electro-magnet electrically connected with the motor circuit for holding the tripping means against the action of the spring, whereby failure of power to the motor will cause the'magnet to be deenergized and allow the spring to move the trippingmeans against the trip arm and release the dowser.

9. In combination with a motion picture projector having a belt for driving the film moving mechanism and a safety device having a trip adapted to release a dowser and allow same to swing into the path of the rays of light passing through the film, means for actuating said safety device including tripping means adjacent the trip arm, a spring tending tomove the tripping means against the trip arm, an electro-magnet holding the tripping means against the action of the spring, an electrical, circuit for energizing the magnet, a switch in said circuit, and means coacting with the belt for opening the switch should the belt break whereby the magnet will be deenergized and the spring allowed to move the tripping means against the trip arm and release the dowser.

10. In combination with a motion picture projector having a'motor circuit and a belt r driving the film moving mechanism and a safety device having a trip adapted to re lease a dowser and allow same to swing into the path of the rays of light passing through the film, means for actuating said safety de'- vice including tripping means adjacent the trip arm, a spring'tending to move the tripping. means against the trip arm, an electromagnet electrically connected with the motor circuit for holding the tripping means against the action of the spring, a switch in the motor circuit, a roller resting against the belt and adapted to open the switch should the whereby the magnet through safety d net armat support, a spring ten erid of the armature away d and the spri means aga ns with a m0t1 motor circuit and a belt moving mecha ng a tripadapte nd allow same to swing the film, means dmg misuse ng allowe t the trip on pictiire the and cause it to trip the triparm, an electromagnet electrically connected with the" motor d circuit for holding the armature against the action oi the spring, a switch in the motor c op 7 whereby the breaking of a belt or failure nism and of power to the motor will cause the magnet' d to. to be deenergized and the spring allowed to f swing the armature and cause the trip arm'- to be actuated.

In'testimony whereof .we have signed our L names to this specification.

THOMAS LEWIS FEENEY. HUMBERT GODQY. 

